How to determine market saturation...

Google  a keyword or phrase your ideal customer is likely to google to find offers like yours. Count how many ads appear on page 1 and compare that count 

0 - First to market 

1-3 Few Competitors 

3-5 Many Competitors 

5+ - Over saturated 

Additional tools: Complete High Profit Problems to craft an offer proven to sell

Remember: Count ads on top, middle and bottom of page 1 search results